What is best way to get and unserialize data in codeigniter?

On my controller I need to be able to get some serialized data but keep on getting error below

A PHP Error was encountered

Severity: Notice
Message: Undefined offset: 0
Filename: common/Dashboard.php
Line Number: 40
Backtrace:

Var dump

string(111) "a:3:{s:7:"user_id";s:2:"20";s:8:"username";s:20:"demo";s:4:"name";s:20:"John Doe";}"

PHP Code:

$results = $this->get_user_activities();

foreach ($results as $result) {

$var = $result['data'];

var_dump($var);

$var = unserialize($var);

echo $var[0]; // Should echo user_id I would think.

} 


Model Function

PHP Code:

public function get_user_activities() {
$this->db->select('data, date_added');
$this->db->from($this->db->dbprefix . 'user_activity');
$this->db->order_by('date_added', 'DESC');
$query = $this->db->get();
if ($query->num_rows() > 0) {
return $query->result_array();
} else {
return false;
}
} 


How come there is a offset error? And how can I fix it?

There's only one rule - please don't tell anyone to go and read the manual.  Sometimes the manual just SUCKS!

I am just confused on the best way

I tried this code below for getting seems to work but not sure if safe

PHP Code:

$key = unserialize($result['data']); 


PHP Code:

foreach ($results as $result) {
$this->lang->load('dashboard/user_activity', 'english');

$key = unserialize($result['data']);

$data['activities'][] = array(
'comment' => anchor('user/user/' . $key['user_id'], $key['name']) .' '. $this->lang->line('text_' . $result['key']),
'date_added' => date($this->lang->line('datetime_format'), strtotime($result['date_added']))
);
} 


There's only one rule - please don't tell anyone to go and read the manual.  Sometimes the manual just SUCKS!

How come there is a offset error? And how can I fix it?

Your array $var doesn't have a key called 0.
echo $var['user_id'];  should give you the userid you're looking for.